Display apparatus including a plurality of banks and a method of manufacturing the same

ABSTRACT

A display apparatus is provided including a first substrate on which a plurality of organic light-emitting diodes are arranged. A second substrate is bonded to the first substrate. The second substrate includes a plurality of light control units respectively corresponding to the plurality of organic light-emitting diodes and a plurality of banks arranged between the plurality of light control units. The plurality of banks include a first bank having a deflection arrangement structure in which a fluorine-containing polymer is concentrated on a surface of a side of the first bank, and a second bank that does not have a deflection arrangement structure in which the fluorine-containing polymer is deflectively arranged.

CROSS-REFERENCE TO RELATED APPLICATION

This U.S. non-provisional patent application claims priority under 35U.S.C. § 119 to Korean Patent Application No. 10-2019-0045136, filed onApr. 17, 2019, in the Korean Intellectual Property Office, thedisclosure of which is incorporated by reference herein in its entirety.

1. Technical Field

Exemplary embodiments of the present invention relate to a displayapparatus and more particularly, to a display apparatus including aplurality of banks and a method of manufacturing the same.

2. Discussion of Related Art

A display apparatus such as an organic light-emitting display apparatustransmits an image by generating light based on a principle in which ahole and an electron injected from an anode and a cathode, respectively,recombine with each other in a light-emitting layer to thereby produceexcitons and emit light. For example, the display apparatus includespixels emitting light of a color among red, green, and blue, andcombines colors of the pixels with each other to thereby produce adesired color of light.

Each of the pixels includes an organic light-emitting diode configuredto generate monochromatic light such as white light or blue light, and aquantum-dot thin-film layer, a color filter layer, etc. Light controlunits are provided which convert the monochromatic light into light of adesired color among red, green and blue, and emit the converted light.For example, when the organic light-emitting diode of each of the pixelsgenerates monochromatic light, the monochromatic light passes throughthe quantum-dot thin-film layer and the color filter. The monochromaticlight is converted into light of a color among red, green, and blue tobe emitted. Thus, an image with a desired color may be transmitted bycombining proper colors of the emitted light of each of the pixels.

SUMMARY

A bank defining a boundary between pixels is arranged between the lightcontrol units. A phenomenon in which the bank is damaged frequentlyoccurs, and thus, the boundary between the pixels disappears. Since thelight control units are therefore arranged without a boundarytherebetween, the light control units may not be accurately arranged.Thus, there is a high possibility that a defect of a color mixturebetween adjacent pixels may result.

According to an exemplary embodiment of the present invention, a displayapparatus is provided including a first substrate on which a pluralityof organic light-emitting diodes are arranged. A second substrate isbonded to the first substrate. The second substrate includes a pluralityof light control units respectively corresponding to the plurality oforganic light-emitting diodes and a plurality of banks arranged betweenthe plurality of light control units. The plurality of banks include afirst bank having a deflection arrangement structure in which afluorine-containing polymer is concentrated on a surface of a side ofthe first bank, and a second bank that does not have a deflectionarrangement structure in which the fluorine-containing polymer isdeflectively arranged.

According to an exemplary embodiment of the present invention, thefluorine-containing polymer in the first bank is deflectively arrangedon the surface the first bank which is opposite to the second substrate.

According to an exemplary embodiment of the present invention thefluorine-containing polymer comprises perfluoropolyether (PFPE).

According to an exemplary embodiment of the present invention, thesurface on which the fluorine-containing polymer is deflectivelyarranged is liquid-repellent.

According to an exemplary embodiment of the present invention, thesecond bank is provided comprised of perfluoropolyether (PFPE), acryl,silicon, and/or epoxy.

According to an exemplary embodiment of the present invention, a coatinglayer is provided on a surface of the second bank corresponding to thesurface of the first bank.

According to an exemplary embodiment of the present invention, thecoating layer comprises a liquid-repellent material.

According to an exemplary embodiment of the present invention, athin-film encapsulation layer is provided covering the plurality oforganic light-emitting diodes.

According to an exemplary embodiment of the present invention, theplurality of organic light-emitting diodes all generate blue light.

According to an exemplary embodiment of the present invention, theplurality of light control units comprise a quantum-dot thin-film layerconfigured to change a color of light generated from the plurality oforganic light-emitting diodes and/or a color filter layer configured toincrease color purity of the light.

According to an exemplary embodiment of the present invention, a methodof manufacturing an organic light-emitting display apparatus is providedin which a plurality of organic light-emitting diodes are formed on afirst substrate. A plurality of color filter layers are respectivelyformed corresponding to the plurality of organic light-emitting diodeson a second substrate. A plurality of first banks are formed atpositions between the plurality of color filter layers on the secondsubstrate. Damaged first banks are repaired by forming second banks atpositions where the first banks are damaged. A quantum-dot thin-filmlayer is formed on the plurality of color filter layers, and the firstsubstrate is bonded to the second substrate.

According to an exemplary embodiment of the present invention, theplurality of first banks are formed by coating the second substrate witha composite polymer, wherein the composite polymer includes afluorine-containing polymer and a non-fluorine-containing polymer. Thefluorine-containing polymer on surfaces of the plurality of first banksare formed by heating the composite polymer, and leaving the compositepolymer at the positions between the plurality of color filter layers bypatterning the composite polymer.

According to an exemplary embodiment of the present invention, thefluorine-containing polymer comprises perfluoropolyether (PFPE).

According to an exemplary embodiment of the present invention, aliquid-repellent coating layer is formed on a surface of the second bankcorresponding to the surfaces of the plurality of first banks.

According to an exemplary embodiment of the present invention, theforming of the second bank includes arranging a mask, in which anopening is formed, on the second substrate, and injecting a material ofthe second bank in the opening.

According to an exemplary embodiment of the present invention, theinjecting of the material of the second bank includes melting thematerial of the second bank into the opening by irradiating the materialof the second bank with a laser beam, or extruding the material of thesecond bank into the opening by pressing the material of the secondbank.

According to an exemplary embodiment of the present invention, thematerial of the second bank comprises perfluoropolyether (PFPE), acryl,silicon and/or epoxy.

According to an exemplary embodiment of the present invention, theplurality of organic-light emitting diodes generate blue light, and thequantum-dot thin-film layer is formed at a position where the color ofthe blue light is to be changed.

According to an exemplary embodiment of the present invention, thequantum-dot thin-film layer changes a color of the light generated by anorganic light-emitting diode of the plurality of organic light-emittingdiodes, and the plurality of color filter layers increase color purityof the light.

According to an exemplary embodiment of the present invention, athin-film encapsulation layer is provided covering the plurality oforganic light-emitting diodes.

BRIEF DESCRIPTION OF THE FIGURES

The above and other features and aspects of the present invention willbecome more apparent from the following detailed description ofexemplary embodiments taken in conjunction with the accompanyingdrawings, in which:

FIG. 1 is a cross-sectional view illustrating a display apparatusaccording to an exemplary embodiment of the present invention;

FIGS. 2A and 2B are cross-sectional views illustrating a repair processwhen a bank included in the display apparatus of FIG. 1 is damaged;

FIGS. 3A to 3G are cross-sectional views sequentially illustrating aprocess of manufacturing the display apparatus of FIG. 1; and

FIG. 4 is a cross-sectional view illustrating a display apparatusaccording to an exemplary embodiment of the present invention.

DETAILED DESCRIPTION OF THE EMBODIMENTS

Reference will now be made in detail to exemplary embodiments of thepresent invention, examples of which are illustrated in the accompanyingdrawings. Like reference numerals may refer to like elements throughoutthe following detailed description. Although exemplary embodiments aredescribed hereafter, the present invention may have various differentforms and should not be construed as being limited to the descriptionsand illustrations of the exemplary embodiments as set forth herein.

It will be understood that although the terms “first”, “second”, etc.may be used herein to describe various components, these componentsshould not be limited by these terms. These components are only used todistinguish one component from another.

As used herein, the singular forms “a,” “an” and “the” are intended toinclude the plural forms as well, unless the context clearly indicatesotherwise.

It will be further understood that the terms “comprises” and/or“comprising” used herein specify the presence of stated features orcomponents, but do not preclude the presence or addition of one or moreother features or components.

Sizes of elements in the drawings may be exaggerated for convenience ofexplanation. In other words, since sizes and thicknesses of componentsin the drawings may be illustrated for convenience of explanation, thepresent invention may be embodied differently from the exemplaryembodiments illustrated in the figures.

A specific process order may be performed in a different sequence fromthe described order. For example, two consecutively described processesmay be performed substantially at the same time or performed in an orderopposite to the described order.

It will be understood that when a layer, region, or component isreferred to as being “connected to” or “coupled to” another layer,region, or component, it may be “directly connected or coupled” to theother layer, region, or component, or “indirectly connected to” theother layer, region, or component with intervening elementstherebetween. For example, when a layer, region, or component isreferred to as being electrically “connected to” or “coupled to” anotherlayer, region, or component, it may be electrically “directly connectedor coupled” to the other layer, region, or component, or electrically“indirectly connected to” the other layer, region, or component withintervening elements therebetween.

FIG. 1 is a cross-sectional view of a display apparatus according to anexemplary embodiment of the present invention. Here, a set of pixels ofthree colors including red, green, and blue pixels are shown. However,the present invention is not limited thereto, and the colors andquantity of pixels belonging to each set of pixels may be variouslychanged.

As shown in FIG. 1, the display apparatus according to an exemplaryembodiment of the present invention has a structure in which a firstsubstrate 110 is bonded to a second substrate 210 with a filler 300therebetween. An organic light-emitting diode 120 is arranged on thefirst substrate 110, and light control units including quantum-dotthin-film layers 230R and 230G and color filter layers 220R, 220G, and220W are arranged on the second substrate 210.

The organic light-emitting diode 120 has a structure in which an organiclight-emitting layer 123 is arranged between an anode electrode 122 anda cathode electrode 124. The organic light-emitting diode 120 generateslight according to a principle in which a hole and an electron injectedfrom the two electrodes including the anode electrode 122 and thecathode electrode 124, respectively, recombine with each other in theorganic light-emitting layer 123 to thereby produce excitons that emitlight. The organic light-emitting diode 120 generates blue light, andthe light control units of each of the red, green, and blue pixelsconvert the blue light into red, green, and blue light, respectively.

A pixel circuit 121 is connected to the anode electrode 122. The pixelcircuit 121 includes elements such as a thin-film transistor and acapacitor. A thin-film encapsulation layer 130 is provided covering theorganic light-emitting diode 120 and may protect the organiclight-emitting diode 120. The thin-film encapsulation layer 130 may be asingle layer including an organic layer or an inorganic layer or mayinclude multiple layers in which an organic layer and an inorganic layerare stacked alternately. The inorganic layer may include silicon oxide,silicon nitride, and/or silicon oxynitride. The organic layer mayinclude polyethylene terephthalate, polyethylene naphthalate,polycarbonate, polyimide, polyethylene sulfonate, polyoxymethylene,polyarylate, hexamethyldisiloxane, and/or an acrylic-based resin (e.g.,polymethyl methacrylate, polyacrylic acid, etc.).

The light control units include the quantum-dot thin-film layers 230Rand 230G and the color filter layers 220R, 220G, and 220W. Thequantum-dot thin-film layers 230R and 230G convert blue light generatedfrom the organic light-emitting diode 120 into light of a desired colorsuch as red or green. The color filter layers 220R, 220G, and 220W mayfilter stray light that may be partially mixed from a conversion result,for example, a color such as red or green, to thereby increase a colorpurity. Here, while the red pixel and the green pixel each include boththe quantum-dot thin-film layers 230R and 230G and the color filterlayers 220R and 220G, respectively, the blue pixel includes only thecolor filter layer 220W of a white color. This is because blue light isgenerated from the organic light-emitting diode 120. For example, sincethe blue pixel does not need to change a color of light and only needsto transmit the light, the blue pixel includes only the white colorfilter layer 220W for filtering stray light.

A black matrix 250 is arranged between respective pixels. A bank 240defines a boundary between light control units of respective pixels. Forexample, the bank 240 may be disposed between adjacent color filterlayers 220W, 220G and 220R and adjacent quantum-dot thin-film layers230R and 230G.

A surface of a least one of the banks 240 facing the first substrate 110has a liquid-repellent characteristic. Such a liquid-repellentcharacteristic prevents a liquid droplet, sprayed from an ink jet, fromstaining the bank 240 when the quantum-dot thin-film layers 230R and230G are formed by using an ink-jet method in a manufacturing process.

According to an exemplary embodiment of the present invention, the banks240 may have an upper surface that is sloped. For example, the banks 240may have a pyramidal or conical upper surface to help preserve ink andprevent contamination of adjacent pixels during ink-jet manufacturing.

According to an exemplary embodiment of the present invention, theslopes of the banks 240 may extend upward and opposite to one anotheraway from the second substrate 210, thus ink run off may be contained ina valley formed between the upward extending slopes.

The at least one bank 240 has a deflection arrangement structure inwhich a fluorine-containing polymer in the bank 240 is concentrated on asurface of the at least one bank 240. For example, thefluorine-containing polymer on the at least one bank 240 may be disposedon an upper surface of the at least one bank 240. However, at least oneof the banks 240 might not have such a deflection arrangement structure.The at least one bank 240 that does not have the deflection arrangementstructure may be a repair bank generated by forming the bank 240 a (See,e.g., FIGS. 2A and 2B) at a position where a bank 240 has been damaged.

Hereinafter, banks having a deflection arrangement structure may also bereferred to as first banks, and the repair banks may also be referred toas second banks. FIGS. 2A and 2B illustrate a repair process of formingsecond banks 240 a in a position where a first bank 240 has beendamaged. For example, as shown in FIG. 2A, a mask 410 is arranged on thesecond substrate 210 to match an opening 411 with a position in whichthe repairing is to be performed. Then, a material 240 a-1 of the secondbank 240 a is placed on the opening 411 and a beam of a laser 400 isemitted toward the material 240 a-1 so that the material 240 a-1 ismelted into the opening 411. Thus, the second bank 240 a may be formed.Alternatively, as shown in FIG. 2B, a mask 510 is arranged on the secondsubstrate 210 and may expose an opening 511 in a position correspondingto a position in which repairing is to be performed. Then, a material240 a-1 of the second bank 240 a is placed on the opening 511 andpressed by a presser 500. Accordingly, the material 240 a-1 is pushedinto the opening 511 and extruded to thereby form the second bank 240 a.

Then, the second bank 240 a is formed by performing a repair at aposition where the first bank 240 is damaged. Accordingly, a boundarybetween pixels might not collapse, and thus, color mixture may beeffectively prevented. A detailed process of manufacturing the first andsecond banks 240 and 240 a will be described later on herein.

Then, a filler 300 is disposed on the first substrate 110 or the secondsubstrate 210 and covers the first and second banks 240 and 240 a. Forexample, the filler 300 may be arranged between the first substrate 110and the second substrate 210, wherein the filler 300 may function asboth a gap spacer maintaining a proper space between the first andsecond substrates 110 and 210 and a bonding material. Accordingly, whenthe filler 300 is applied to bond the first substrate 110 and the secondsubstrate 210, the filler 300 properly maintains a gap between the firstand second substrates 110 and 210 and firmly couples the first substrate110 to the second substrate 210.

A display apparatus having the above-described structure may bemanufactured by using a process shown in FIGS. 3A to 3G.

First, shown in FIG. 3A, the organic light-emitting diode 120 is formedon the first substrate 110, and then, a thin-film encapsulation layer130 is formed covering the organic light-emitting diode 120.

Next, as shown in FIG. 38, the black matrix 250 and the color filterlayers 220R, 220G, and 220W are formed on the second substrate 210 byusing a photolithography process. The color filter layers 220R, 220G,and 220W are each formed in a position corresponding to an organiclight-emitting diode 120.

Then, as shown in FIG. 3C, the composite polymer 240-1 in which thefluorine-containing polymer 240-1 a containing fluorine (F) is mixedwith the non-fluorine-containing polymer 240-1 b that does not containfluorine is prepared and coated on the color filter layers 220R, 220G,and 220W and the black matrix 250, and then heated. For example, acomposite polymer 240-1, in which a fluorine-containing polymer 240-1 asuch as perfluoropolyether (PFPE) is mixed with anon-fluorine-containing polymer 240-1 b such as acryl, silicon, and/orepoxy, is coated on upper portions of the color filter layers 220R,220G, and 220W and the black matrix 250 and then heated. The compositepolymer 240-1 is a material that becomes the first bank 240 later onafter further processing. When the composite polymer 240-1 is heated,the fluorine-containing polymer 240-1 a in the composite polymer 240-1is moved toward a surface of a side of the composite polymer 240-1, andthus, is deflectively arranged.

Deflectively arranged may mean that the fluorine-containing polymer240-1 a is concentrated on one surface resulting in a non-uniformdistribution, as in the first bank 240. Otherwise, it may be ahomogenous distribution of the fluorine-containing polymer as a whole,as in the second bank 240 a. Also, the repaired second banks 240 a mayhave a different material than the first banks 240. After heating, thefluorine containing polymer 240-1 a may form an outer surface of thecomposite polymer 240-1 disposed opposite to the second substrate 210and may have a polymer structure in which fluorine containing monomersare arranged in a staggered configuration.

Accordingly, the surface of the composite polymer 240-1 on which thefluorine-containing polymer 240-1 a is concentrated has liquid-repellentcharacteristics.

In addition, as shown in FIG. 3D, the composite polymer 240-1 ispatterned to remain in each position between the color filter layers220R, 220G, and 220W of each pixel. For example, the composite polymer240-1 may be etched to produce the first banks 240. The first banks 240are arranged as a boundary between respective pixels. A phenomenon inwhich first banks 240 in some positions between the respective pixelsare damaged may occur after the coating, the heating, and/or thepatterning are performed. This may be detected by a process ofinspection through use of a camera after the first bank 240 ispatterned. FIG. 3D illustrates an example in which the first bank 240between the color filter layers 220R and 220G is damaged.

When the damage of the first bank 240 is detected, a repair operation isperformed at a position of the damaged first bank 240 by forming thesecond bank 240 a, as shown in FIG. 3E. A method of performing therepairing is described with reference to FIGS. 2A and 28. That is, themask 410 or 510 is placed on the second substrate 210 to match theopening 411 or 511 at a position of the damage. Then, the material 240a-1 is injected via the opening 411 or 511 by using the laser 400 or thepresser 500 to thereby form the second bank 240 a. The material 240 a-1of the second bank 240 a may include a same composite polymer as that ofthe first bank 240; PFPE having liquid-repellent characteristics andacryl, silicon, and/or epoxy having non-liquid-repellentcharacteristics. The second bank 240 a is generated as a repair bankthrough melting or extrusion in positions where the first bank 240 isdamaged. Unlike the first bank 240, a heat treatment process ofdeflectively arranging a fluorine-containing polymer is not separatelyperformed. Accordingly, a fluorine-containing polymer does not alwaysneed to be used. Also, the second bank 240 a does not need to be aliquid-repellent material. Since a probability of the damage of thefirst bank 240 occurring is generally 1/10,000, whether the second bank240 a is liquid-repellent or non-liquid-repellent may have a low impacton the quality of a display apparatus. However, when a surface of thesecond bank 240 a has liquid-repellent characteristics, a more stablequality of the product may be ensured. To do so, as shown in FIG. 3E,forming a liquid-repellent coating layer 240 a′ including a PFPEmaterial on a surface of the second bank 240 a may be further included.A stable bank structure is thereby obtained.

Then, as shown in FIG. 3F, quantum-dot thin-film layers 230R and 230Gare formed selectively on a red pixel and a green pixel, but might notbe formed on a blue pixel. In this case, the quantum-dot thin-filmlayers 230R and 230G are formed in positions overlapping the colorfilter layers 220R and 220G, respectively. The quantum-dot thin-filmlayers 230R and 230G may be formed by using an ink-jet process. Since aboundary between pixels is clearly defined by the first and second banks240 and 240 a, there is no possibility that color mixture may occurduring the ink-jet process.

A quantum dot or a core that is a light color-change particle includedin the quantum-dot thin-film layers 230R and 230G may include a GroupII-VI compound, a Group III-V compound, a Group IV-VI compound, a GroupIV element and/or a Group IV compound.

The Group II-VI compound may include a binary compound such as cadmiumselenide (CdSe), cadmium telluride (CdTe), zinc sulfide (ZnS), zincselenide (ZnSe), zinc telluride (ZnTe), zinc oxide (ZnO), mercurysulfide (HgS), mercury selenide (HgSe), mercury telluride (HgTe),magnesium selenide (MgSe) and/or magnesium sulfide (MgS); a ternarycompound such as silver-indium-sulfide (AgnS), copper-indium-sulfur(CuInS), cadmium selenide sulphide (CdSeS), cadmium selenotelluride(CdSeTe), cadmium sulfur telluride (CdSTe), zinc selenium sulfide(ZnSeS), zinc selenide telluride (ZnSeTe), zinc sulfide telluride(ZnSTe), mercury selenium sulfide (HgSeS), mercury selenium telluride(HgSeTe), mercury sulfide telluride (HgSTe), cadmium zinc sulfide(CdZnS), cadmium zinc selenide (CdZnSe), cadmium zinc telluride(CdZnTe), cadmium mercury sulfide (CdHgS), cadmium mercury selenide(CdHgSe), cadmium mercury telluride (CdHgTe), mercury zinc sulfide(HgZnS), mercury zinc selenide (HgZnSe), mercury zinc telluride(HgZnTe), magnesium zinc selenide (MgZnSe) and/or magnesium zinc sulfide(MgZnS); and/or a quaternary compound such as zinc telluride sulfide(HgZnTeS), cadmium zinc selenide sulfide (CdZnSeS), cadmium zincselenium telluride (CdZnSeTe), cadmium zinc sulfide telluride (CdZnSTe),cadmium mercury selenium sulfide (CdHgSeS), cadmium mercury seleniumtelluride (CdHgSeTe), cadmium mercury sulfide telluride (CdHgSTe),mercury zinc selenium sulfide (HgZnSeS), mercury zinc selenium telluride(HgZnSeTe) and/or mercury zinc sulfide telluride (HgZnSTe).

The Group III-V compound may be selected from a binary compound such asgallium nitride (GaN), gallium phosphide (GaP), gallium arsenide (GaAs),gallium antimonide (GaSb), aluminum nitride (AlN), aluminum phosphide(AlP), aluminum arsenide (AlAs), aluminum antimonide (AlSb), indiumnitride (InN), indium phosphide (InP), indium arsenide (InAs) and/orindium antimonide (InSb); and/or a ternary compound such asgallium-nanoparticles (GaNP), aluminum-nitride-arsenic (GaNAs), galliumnitride antimonide (GaNSb), gallium phosphide arsenide (GaPAs), galliumphosphide antimonide (GaPSb), alumina nanoparticles (AlNP),aluminum-nitride-arsenic (AlNAs), AlNSb, aluminum phosphide arsenide(AlPAs), aluminum phosphide antimonide (AlPSb), indium gallium phosphide(InGaP), indium nanoparticle (InNP), InNAs, InNSb, indium phosphidearsenide (InPAs), indium phosphide antimonide (InPSb) and/or galliumalumina nanoparticles (GaAlNP); and/or a quaternary element selectedfrom a group consisting of GaAlNAs, GaAlNSb, gallium aluminum phosphidearsenide (GaAlPAs), gallium aluminum phosphide antimonide (GaAlPSb),GaInNP, GaInNAs, GaInNSb, gallium indium phosphide arsenide (GaInPAs),gallium indium phosphide antimonide (GaInPSb), InAlNP, InAlNAs, InANSb,indium aluminum phosphide arsenide (InAlPAs) and/or indium aluminumphosphide antimonide (InAlPSb).

The Group IV-VI compound include a binary compound selected from a groupconsisting of tin sulfide (SnS), tin selenide (SnSe), tin telluride(SnTe), lead(II) sulfide, lead Selenide (PbSe) and/or lead telluiide(PbTe); and/or a ternary compound selected from a group consisting oftin selenium sulfide (SnSeS), tin selenium telluride (SnSeTe), tinsulphotelluride (SnSTe), lead selenium sulfide (PbSeS), lead seleniumtelluride (PbSeTe), lead sulfide telluride (PbSTe), tin lead sulfide(SnPbS), tin lead selenide (SnPbSe) and/or tin lead telluride (SnPbTe);and/or a quaternary compound selected from tin lead sulfide selenide(SnPbSSe), tin lead selenium telluride (SnPbSeTe) and/or tin leadsulfide telluride (SnPbSTe). The Group IV element include silicon (Si)and/or germanium (Ge). The Group IV compound is a silicon carbide (SiC)and/or silicon-germanium (SiGe).

In this case, the binary compound, the ternary compound, and/or thequaternary compound may be present in a particle at a uniformconcentration, or may be in a same particle but in different states withpartially different concentration distributions. In addition, the binarycompound, the ternary compound, and/or the quaternary compound may havea core/shell structure in which a quantum dot surrounds another quantumdot. An interface between the core and the shell may include aconcentration gradient in which a concentration of an element present inthe shell is increasingly reduced toward a center of the core.

According to an exemplary embodiment of the present invention a quantumdot may have a core-shell structure that includes a core including ananocrystal described above and a shell surrounding the core. A shell ofthe quantum dot may function as a protective layer configured tomaintain semiconductor characteristics by preventing chemicalmodification of the core and/or as a charging layer configured toprovide electrophoresis characteristics to the quantum dot. The shellmay include a single layer or multiple layers. An interface between thecore and the shell may include a concentration gradient in which aconcentration of an element present in the shell is increasingly reducedtoward a center of the core. Examples of the shell of the quantum dotmay include an oxide of a metal or a non-metal, and/or semiconductorcompound.

For example, the oxide of a metal or a non-metal may include a binarycompound such as silicon oxide (SiO₂), aluminum oxide (AlO₃), titaniumdioxide (TiO₂), zinc oxide (ZnO), manganese(II) oxide (MnO),manganese(III) oxide (Mn₂O₃), manganese(II,III) oxide (MnO₄), cupricoxide (CuO), iron(II) oxide (FeO), iron(II) oxide (Fe₂O₃), iron(II,II)oxide (Fe₂O₄), cobalt(II) oxide (CoO), cobalt (II,III) oxide (Co₂O₄)and/or nickel oxide (NiO) and/or a tertiary compound such as magnesiumaluminate (MgAl₂O₄), cobalt iron oxide (CoFe₂O₄), nickel(II) iron(III)oxide (NiFe₂O₄) and/or cobalt-manganese oxide (CoMn₂O₄). However, thepresent invention is not limited thereto.

In addition, the semiconductor compound may include cadmium sulfide(CdS), CdSe, CdTe, ZnS, ZnSe, ZnTe, ZnSeS, zinc telluride sulfide(ZnTeS), GaAs, GaP, GaSb, mercury(II) sulfide (HgS), HgSe, HgTe, InAs,InP, InGaP, InSb, AlAs, AlP and/or AlSb. However, the present inventionis not limited thereto.

A quantum dot may have a full width at half maximum (FWHM) ofalight-emitting wavelength spectrum of about 45 nm or less, about 40 nmor less, or about 30 nm or less. In such a range, color purity or gamutmay be enhanced. In addition, since light emitted through the quantumdot is emitted in an omni-direction, a light viewing angle may beenhanced.

In addition, the quantum dot has a form generally used in the art towhich the present invention belongs, and is not particularly limited.However, in detail, the quantum dot may have a shape such as a sphere, apyramid, a multi-armed shape or a cubic nanoparticle, a nanotube, ananowire, a nanofiber, and/or a nanoplate particle.

The quantum dot may adjust a color of emitted light according to aparticle size. Accordingly, the quantum dot may have various colors ofemitted light such as blue, red, green, etc.

After the quantum-dot thin-film layers 230R and 230G are formed as shownin FIG. 3F, the filler 300 is applied between the first and secondsubstrates 110 and 210, and then, the first substrate 110 is bonded tothe second substrate 210, as shown in FIG. 3G. Then, as shown in FIG. 1,the display apparatus including the organic light-emitting diode 120,the quantum-dot thin-film layers 230R and 230G, and the color filterlayers 220R, 220G, and 220W is implemented.

In addition, the first and second banks 240 and 240 a clearly define aboundary between respective pixels, thus a defect that may be caused bycolor mixture rarely occurs. Accordingly, the display apparatus havingvery stable color quality may be implemented.

According to an exemplary embodiment of the present invention, theorganic light-emitting layer 123 of the organic light-emitting diode 120may be formed as a common layer over a whole pixel area is shown as anexample in FIG. 1. As shown in FIG. 4, however, a modified example isillustrated in which the organic light-emitting layer 123 is arrangedseparately for each pixel. For example, it is shown in FIG. 4 that theorganic light-emitting layer 123 may be arranged separately for eachpixel and the cathode electrode 124 may be disposed directly onnon-light emitting regions between pixels and a surface of the organiclight-emitting layer 123. In this case, the first and second banks 240and 240 a may be firmly maintained to prevent color mixture.

As described above according to the display apparatus and a method ofmanufacturing the same according to exemplary embodiments of the presentinvention, a bank damaged during a manufacture process may be quicklyand efficiently repaired. Thus, an image of clean and clear colors maybe implemented by obstructing color mixture that may be caused by damageto the banks. Thus, performance and reliability of a display apparatusmay be increased.

While the present invention has been shown and described with referenceto exemplary embodiments thereof, it should be understood by those ofordinary skill in the art that various modifications may be made theretowithout departing from the spirit and scope of the present invention asdefined by the appended claims.

What is claimed is:
 1. A display apparatus, comprising: a firstsubstrate on which a plurality of organic light-emitting diodes arearranged; and a second substrate bonded to the first substrate, whereinthe second substrate comprises a plurality of light control unitsrespectively corresponding to the plurality of organic light-emittingdiodes and a plurality of banks arranged between the plurality of lightcontrol units, wherein the plurality of banks comprise: a first bankhaving a deflection arrangement structure in which a fluorine-containingpolymer is concentrated on a surface of a side of the first bank; and asecond bank that does not have a deflection arrangement structure inwhich the fluorine-containing polymer is deflectively arranged.
 2. Thedisplay apparatus of claim 1, wherein the fluorine-containing polymer inthe first bank is deflectively arranged on the surface of the side ofthe first bank which is opposite to the second substrate.
 3. The displayapparatus of claim 1, wherein the fluorine-containing polymer comprisesperfluoropolyether (PFPE).
 4. The display apparatus of claim 1, whereinthe surface of the side on which the fluorine-containing polymer isdeflectively arranged is liquid-repellent.
 5. The display apparatus ofclaim 1, wherein the second bank is comprised of perfluoropolyether(PFPE), acryl, silicon, and/or epoxy.
 6. The display apparatus of claim1, further comprising a coating layer on a surface of the second bankcorresponding to the surface of the side of the first bank.
 7. Thedisplay apparatus of claim 6, wherein the coating layer comprises aliquid-repellent material.
 8. The display apparatus of claim 1, furthercomprising a thin-film encapsulation layer covering the plurality oforganic light-emitting diodes.
 9. The display apparatus of claim 1,wherein the plurality of organic light-emitting diodes all generate bluelight.
 10. The display apparatus of claim 1, wherein the plurality oflight control units comprise a quantum-dot thin-film layer configured tochange a color of light generated from the plurality of organiclight-emitting diodes and/or a color filter layer configured to increasecolor purity of the light.
 11. A method of manufacturing an organiclight-emitting display apparatus, comprising: forming a plurality oforganic light-emitting diodes on a first substrate; forming a pluralityof color filter layers respectively corresponding to the plurality oforganic light-emitting diodes on a second substrate; forming a pluralityof first banks at positions between the plurality of color filter layerson the second substrate; repairing damaged first banks by forming secondbanks at positions where the first banks are damaged; forming aquantum-dot thin-film layer on the plurality of color filter layers; andbonding the first substrate to the second substrate.
 12. The method ofclaim 11, wherein the forming of the plurality of first banks comprisescoating the second substrate with a composite polymer, wherein thecomposite polymer includes a fluorine-containing polymer and anon-fluorine-containing polymer; and arranging the fluorine-containingpolymer on surfaces of the plurality of first banks by heating thecomposite polymer, and leaving the composite polymer at the positionsbetween the plurality of color filter layers by patterning the compositepolymer.
 13. The method of claim 12, wherein the fluorine-containingpolymer comprises perfluoropolyether (PFPE).
 14. The method of claim 12,further comprising forming a liquid-repellent coating layer on a surfaceof the second bank corresponding to the surfaces of the plurality offirst banks.
 15. The method of claim 11, wherein the forming of thesecond bank comprises arranging a mask, in which an opening is formed,on the second substrate, and injecting a material of the second bank inthe opening.
 16. The method of claim 15, wherein the injecting of thematerial of the second bank comprises: melting the material of thesecond bank into the opening by irradiating the material of the secondbank with a laser beam, or extruding the material of the second bankinto the opening by pressing the material of the second bank.
 17. Themethod of claim 15, wherein the material of the second bank comprisesperfluoropolyether (PFPE), acryl, silicon and/or epoxy.
 18. The methodof claim 11, wherein the plurality of organic-light emitting diodesgenerate blue light, and wherein the quantum-dot thin-film layer isformed at a position where the color of the blue light is to be changed.19. The method of claim 11, wherein the quantum-dot thin-film layerchanges a color of the light generated by an organic light-emittingdiode of the plurality of organic light-emitting diodes, and theplurality of color filter layers increase color purity of the light. 20.The method of claim 11, further comprising a thin-film encapsulationlayer covering the plurality of organic light-emitting diodes.